Vehicle provided with inclination sensor

ABSTRACT

To prevent an inclination sensor of a vehicle from becoming soiled by flying matter such as muddy water splashes scattered by the rotating wheels of the vehicle itself, which may result in false detection of the inclination of the vehicle to a road surface, a vehicle provided with an inclination sensor for detecting the inclination of vehicle to road surface is proposed, wherein the sensor is attached onto the undersurface of the vehicle at a position between the wheels in the direction of the width of the vehicle, and a cover member having at least either of a side cover portion for covering the wheel side of the inclination sensor or a rear side portion for covering the rear side of the inclination sensor in the longitudinal direction of the vehicle is provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/939,951, filed Sep. 13, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to a vehicle provided with aninclination sensor for detecting the state of inclination of thevehicle, particularly provided with an inclination sensor provided witha cover member for intercepting flying matter such as a splash of muddywater which may run into the inclination sensor.

2. Description of the Related Art

In recent years, in a heavy vehicle such as a truck provided with aheadlight of high brightness, a light axis adjusting device is provided.This device adjusts the light axis automatically in accordance with thetilt of the vehicle to a road surface, which is detected by aninclination sensor, in order to prevent the driver of an oncoming carfrom being dazzled by the strong light.

One such light axis adjusting device is disclosed in Japanese Laid-OpenPatent Application No. 2003-127757 (hereafter referred as patentliterature 1). According to the art disclosed in patent literature 1,two pairs of an ultrasonic wave radiator and a detector are locatedalong the longitudinal direction of the vehicle with a certain distanceapart from each other, each pair consisting of an ultrasonic waveradiator for radiating an ultrasonic wave toward a road surface and adetector for detecting the ultrasonic wave reflected from the roadsurface to compose a radiator-detector couple. The radiator and detectorare located along the direction of width of the vehicle with a certaindistance from each other. The radiators and detectors are connected to acontroller. The inclination of the vehicle to the road surface iscalculated based on the time difference between the time needed from theradiating ultrasonic wave to the detection of the reflected ultrasonicwave by means of a pair of radiator and detector located in the frontside and the time needed from the radiation of the ultrasonic wave tothe detection of the reflected ultrasonic wave by means of another pairof radiator and detector located in the rear side. The controller allowsthe light axes of head lamps to be changed according to the inclinationof the vehicle detected.

Further, according to the art disclosed in patent literature 1, said twopairs of ultrasonic wave sensors are mounted to a box-like case so thatthe radiating faces and detecting faces of the sensors are exposedtoward the road surface, and the case mounted with the sensors isattached to the central part of the cross member of the vehicle frame.Because of this, the space in the longitudinal direction of the vehiclerequired for attaching the case is decreased, and a compact inclinationsensor is achieved by accommodating the sensors in the case.

SUMMARY OF THE INVENTION

Since the inclination sensor of patent literature 1 is composed suchthat the two pairs of the ultrasonic wave radiators and detectors areattached to the case, and the radiating and detecting faces thereof areexposed to the road surface, the radiating and detecting faces of theultrasonic wave radiators and detectors are apt to be soiled by flyingmatter. Such flying matter might be a splash of muddy water scattered bythe rotating wheels of the running vehicle itself, or muddy water curledup by the front running cars.

The present inventors ascertained that there are two kinds ofcontamination of the radiating faces of radiators and the detectingfaces of detectors. One type is the contamination by a splash phenomenonin which muddy water splashed by the front wheels impinges directlyagainst the radiating faces and detecting faces. Another type is thecontamination due to a spray phenomenon in which the muddy watersplashed by the tires of the front wheels crashes into small particlesas a consequence of an impingement against the wheel houses (or by therotation of the front wheels), and further spreads between the tires andwheel houses like sprayed muddy water, whereby the sprayed muddy wateris conveyed by a stream produced by the rotation of the wheels andadheres to the radiating faces and detecting faces.

Conventionally, as disclosed in patent literature 1, no countermeasureis devised for preventing the inclination sensor from being contaminatedby the splashing and spraying phenomena as mentioned above. Since muddywater splashing onto the inclination sensor is not prevented, theradiating and detecting faces of the ultrasonic wave radiators anddetectors are apt to be soiled. This can cause false detection of theinclination of the vehicle to the road surface.

Therefore, in light of the problem of the prior art, the object of thepresent invention is to provide a vehicle provided with an inclinationsensor which does not become contaminated by flying matter, and hencedoes not provide a false detection of the inclination of the vehicle tothe road surface.

The present invention provides a vehicle provided with an inclinationsensor for detecting an inclination of vehicle to the road surface,wherein said sensor is attached onto the undersurface of the vehicle ata position between the wheels in the direction of the width of thevehicle, and a cover member having at least either a side cover portionfor covering the wheel side of the inclination sensor or a rear sideportion for covering the rear side of the inclination sensor isprovided.

According to the invention, flying matter, such as muddy water splashproduced by said splash phenomenon, is prevented from impinging directlyupon the radiating faces of the radiators and the detecting faces of thedetectors of the ultrasonic wave sensor mainly by the side cover portioncovering the front wheel side of the ultrasonic wave sensor. Thecontamination by the spray phenomenon in which muddy water spray spreadsbetween the front tires and wheel houses is prevented from coming aroundtoward the radiating faces of the radiators and the detecting faces ofthe detectors of the ultrasonic wave sensor by virtue of said side coverportion and the rear side cover portion for covering the rear side ofthe ultrasonic wave sensor.

With respect to the cover member, it is possible that either the sidecover portion or the rear cover portion is provided, although preferablyonly the side cover portion is provided.

In the present invention, it is preferable that the cover member isprovided with a front cover portion for covering the front side of theinclination sensor. With the configuration like this, flying matter suchas a muddy splash spreading in the space between the wheels and wheelhouses can be prevented from coming around the front side of theultrasonic wave sensor to the radiating faces of the radiators and thedetecting faces of the detectors of the ultrasonic wave sensor by thefront cover portion covering the front side of the ultrasonic wavesensor. Further, the splashes caused by front running cars can beintercepted.

In the present invention, it is preferable that said inclination sensoris fixed to the vehicle by a bracket to which said cover member isattached detachably. With the configuration like this, it is easy toremove the cover member from the bracket so that the ultrasonic wavesensor and the cover can be cleaned and again attached. When the coveris damaged, the cover can be replaced easily.

In the present invention, it is preferable that said inclination sensoris an ultrasonic wave sensor comprising ultrasonic wave radiators forradiating the ultrasonic wave, ultrasonic wave detectors for detectingthe ultrasonic wave, and a case in which said ultrasonic wave radiatorsand ultrasonic wave detectors are mounted; said case is formed to haveconically shaped parts which broaden in diameter from each of theultrasonic wave radiators and detectors toward the road surface. Thecover member is located such that the lower end thereof does notinterfere with each of the extension of the conically shaped parts. Withthe configuration like this, the cover member can intercept flyingmatter without interfering with the ultrasonic wave radiated from theultrasonic wave sensor, so accurate detection of the inclination of thevehicle by means of the ultrasonic wave sensor is possible by preventingthe contamination of the inclination sensor.

Further, it is preferable that a head lamp controller is provided forcontrolling the light axes of the head lamps of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to certain preferredembodiments thereof along with the accompanying drawings, wherein:

FIG. 1 is a perspective view showing the ultrasonic wave sensor, thebracket and the cover for intercepting splashes of the first embodiment;

FIG. 2(A) is an exploded view of the bracket and the cover forintercepting splashes, and FIG. 2(B) is a perspective view of anotherembodiment of the bracket;

FIG. 3 is a side view of the heavy truck to which the present inventionis applied;

FIG. 4 is a plan view of the chassis of the heavy truck of FIG. 3;

FIG. 5(A) is a sectional side elevation of the ultrasonic wave sensor,and

FIG. 5(B) is a perspective view of the ultrasonic wave sensor viewedfrom above;

FIG. 6 is a partial plan view showing the inclination sensor with thecover of the second embodiment of the invention fixed to the front partof the vehicle;

FIG. 7 is a perspective view of the cover of the second embodiment ofthe invention; and

FIG. 8(A) and FIG. 8(B) are drawings illustrating the the relativepositions of the ultrasonic wave path and the cover.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of the present invention will now be detailedwith reference to the accompanying drawings. It is intended, however,that unless particularly specified, dimensions, materials, relativepositions and so forth of the constituent parts in the embodiments shallbe interpreted as illustrative only and not as limitative of the scopeof the present invention.

FIG. 1 is a perspective view showing the ultrasonic sensor, the bracketand the cover for intercepting splashes of the first embodiment. FIG.2(A) is an exploded view of the bracket and the cover for interceptingsplashes, and FIG. 2(B) is a perspective view of another embodiment ofthe bracket. FIG. 3 is a side view of the heavy truck to which thepresent invention is applied. FIG. 4 is a plan view of the chassis ofthe heavy truck of FIG. 3. FIG. 5(A) is a sectional side elevation ofthe ultrasonic wave sensor, and FIG. 5(B) is a perspective view of theof the ultrasonic wave sensor viewed from above. FIG. 6 a partial planview showing the inclination sensor with the cover of the secondembodiment of the invention, where the inclination sensor with the coveris fixed to the front part of the vehicle. FIG. 7 is a perspective viewof the cover of the second embodiment of the invention. FIG. 8 (A) andFIG. 8(B) are drawings for explaining the relation of position of theultrasonic wave path and the cover.

Referring to FIG. 3 and FIG. 4, which show an embodiment of the heavytruck provided with the inclination sensor according to the presentinvention, numeral reference 101 is a vehicle (truck), 102 is the cab ofthe vehicle 102, 103 is a load-carrying platform, 104 are front wheels,105 are rear wheels, 106 are side frames, and 108 are cross members.Reference numerals 107 are head lamps of which the directions of lightaxes are adjustable. Reference numeral 1 is an ultrasonic inclinationsensor, of which the detail is explained later, for detecting theinclination of vehicle.

The inclination sensor 1 is located at an inner side from the rightfront wheel 104 and attached to the undersurface of the front crossmember 108 (not necessarily the undersurface of the front cross member,the undersurface of the vehicle frame is permissible) by means of abracket 2 (see FIGS. 1, 2). Reference numeral 3 is a cover memberconsisting of a side cover 3 a and a rear cover 3 b, of which thedetails are explained later. The inclination sensor 1 may be a lasersensor comprising laser beam radiators and detectors.

The composition of the inclination sensor 1 will be explained byreferring to FIG. 5(A) hereafter. The ultrasonic inclination sensor 1comprises a case 1 e (see FIG. 5(A)), radiators 1 a and 1 c, anddetectors 1 b and 1 d. A radiator 1 a and a detector 1 c work as a pair,and a radiator 1 b and a detector 1 d work as a pair. Two pairs ofradiators and detectors are provided. A radiator and a detector of onepair are located along the lateral direction of the vehicle so that theultrasonic wave radiated from a radiator 1 a toward the road surface 100and reflected therefrom is detected by a detector 1 b, and theultrasonic wave radiated from a radiator 1 c toward the road surface 100and reflected therefrom is detected by a detector 1 d. The two pairs arelocated along the longitudinal direction of the vehicle with a certaindistance apart from each other. The radiators 1 a and 1 c and detectors1 b and 1 d are attached to the case 1 at the base part 1 f thereof sothat both the radiating faces and the detecting faces of the radiatorsand detectors, respectively, face toward the road surface 100. The basepart 1 f where the radiators 1 a and 1 c and detectors 1 b and 1 d areattached is covered by a case body 1 g. Conically shaped parts 1 hbroadening in diameter toward the road surface 100 are formed in thecase body 1 g. The downward broadening parts 1 h are provided for eachof the radiators 1 a and 1 c and the detectors 1 b and 1 d. The bottom(i.e. radiator or detector side) of each of the conically shaped parts 1h which broaden downward contact the peripheral part of each of theradiators 1 a and 1 c and the detectors 1 b and 1 d. With thisconfiguration, the ultrasonic wave emanates along the surface of theconically shaped parts 1 h which broaden downward. The broadening anglea of the conically shaped part 1 h is 1200 in the embodiment as shown inFIG. 8, and the diffusion of the ultrasonic wave emanating from theradiator 1 a and 1 c is defined in the range of the cone angle α. Theultrasonic wave radiated from each of the radiators 1 a and 1 c andreflected from the road surface 100 is detected by each of the detectors1 b and 1 d respectively. Signals from the radiators and detectors areinputted into a controller, which is not shown in the drawings. Thecontroller detects the inclination of the vehicle to the road surface100 based on the inputted signals and allows the light axes of the headlamps 107 to be adjusted according to the result of the detection.Therefore, the light axes of the head lamps 107 can be adjusted mostsuitably in accordance with the state of inclination of the vehicle.

FIG. 5(B) is a representation showing the location of the radiators 1 aand 1 c and the detectors 1 b and 1 d, and also showing the state of theultrasonic waves which are radiated and reflected. The ultrasonic wavesensor 1 is provided with a radiator 1 a and a detector 1 b in the frontside and a radiator 1 c and a detector 1 d in the rear side along thelongitudinal direction of the vehicle so that the inclination of thevehicle to the road surface is calculated based on the time differencebetween the time needed from the radiation of the ultrasonic wave to thedetection of the reflected ultrasonic wave by means of a radiator and adetector located in the front side and the time needed from theradiation of the ultrasonic wave to the detection of the reflectedultrasonic wave by means of a radiator and detector located in the rearside.

The ultrasonic sensor, bracket and cover for preventing splash of thefirst embodiment of the invention will be explained referring to FIG. 1and FIG. 2. In the drawings, reference numeral 2 is a bracket made of athin steel plate formed into a box-like shape. The bracket 2 is fixed tothe undersurface of the front cross member 108 by the upper face of thebracket by means of a plurality of bolts 7. It may be fixed to a properposition of the vehicle frame and is not limited to the front crossmember. To the undersurface of the flange part 2 a and 2 b of thebracket 2 is fixed the ultrasonic wave sensor 1 by the base part 1 fformed at the upper part of the case 1 e by means of a plurality ofbolts 4. The bracket 2 may be divided into an upper bracket 21 and alower bracket 20 as shown in FIG. 2(B).

Reference numeral 3 is a cover made of a rubber plate (elastomer, resin,or thin steel plate is permissible) having a side cover portion 3 a forcovering the front wheel side of the ultrasonic wave sensor 1 and a rearcover portion 3 b continuing to the side cover portion 3 a to cover therear side of the ultrasonic wave sensor 1. The cover 3 is attached tothe bracket 2 detachably such that the side cover portion 3 a isattached to the cover attaching part 2 j of the bracket 2 by means of aplurality of bolts 5 (three bolts in this example), and the rear coverportion 3 b is attached to the cover attaching part 2 g of the bracket 2by means of a bolt 6 or a plurality of bolts (one bolt in this example).By attaching the cover 3 detachably to the lower part of the bracket 2for fixing the ultrasonic wave sensor 1 to the vehicle frame, it is easyto remove only the cover 3 from the bracket for fixing the ultrasonicwave sensor 1 when the cover is soiled by splashes of muddy waterwithout removing other members, and the cover can be cleaned and againattached. When the cover is damaged, the cover can be replaced easily.

The present inventors ascertained that there are two kinds ofcontamination of the radiating faces of the radiators 1 a and 1 c andthe detecting faces of the detectors 1 b and 1 d. One is thecontamination by a splash phenomenon in which muddy water from a pool orpuddle splashed by the front wheels 104 impinges directly against theradiating faces and detecting faces and soils the faces as shown byarrow A in FIG. 3. Another is the contamination by a spray phenomenon inwhich the muddy water splashed by the tires of the front wheels 104separates into small particles by an impingement against the wheelhouses or by the rotation of the front wheels 104, which spreads betweenthe tires and the wheel houses like sprayed muddy water, whereby thismuddy water spray is conveyed by the stream produced by the rotation ofthe wheels and further adheres to the radiating faces and detectingfaces, soiling the faces as shown by arrow B in FIG. 3.

In the first embodiment of the invention, the cover 3 has a side coverportion 3 a for covering the front wheel side of the ultrasonic wavesensor 1 and a rear cover portion 3 b continuing to the side coverportion 3a to cover the rear side of the ultrasonic wave sensor 1,flying matter is prevented from impinging directly upon the radiatingfaces of the radiators and the detecting faces of the detectors of theultrasonic wave sensor 1 mainly by the side cover portion 3 a coveringthe front wheel side of the ultrasonic wave sensor 1. The contaminationdue to the spray phenomenon in which muddy water spray spreads betweenthe front tires and wheel house is prevented from coming around towardthe radiating faces of radiators and the detecting faces of detectors ofthe ultrasonic wave sensor 1 by virtue of said side cover portion 3 aand the rear side cover portion 3 b for covering the rear side of theultrasonic wave sensor 1.

By virtue of the interception of flying matter such as muddy watersplashes by the cover 3, the radiating faces of radiators and thedetecting faces of detectors of the ultrasonic wave sensor 1 areprevented from being soiled by the flying matter, and hence theoccurrence of false detection of the inclination of the vehicle due tocontamination of the radiating faces of the radiators and the detectingfaces of the detectors is prevented, and proper adjustment of the lightaxes of head lamps is always possible. With respect to the cover 3, itis permissible that either the side cover portion 3 a or the rear coverportion 3 b is provided, but preferably only the side cover portion 3 ais provided.

In the second embodiment shown in FIG. 6 and FIG. 7, a front coverportion 3 c for covering the front side of the ultrasonic wave sensor 1is provided to said cover 3, in addition to the side cover portion 3 afor covering the front wheel side of the ultrasonic wave sensor 1, therear cover portion 3 b for covering the rear side of the ultrasonic wavesensor 1, the side cover portion 3 a and rear cover portion 3 b, and thefront cover portion 3 c are continued to form a general shape of asideways letter “U.” In the second embodiment, flying matter such as amuddy splash spreading in the space between the front wheels and wheelhouses is prevented from coming around the front side of the ultrasonicwave sensor 1 to the radiating faces of radiators and the detectingfaces of the detectors of the ultrasonic wave sensor 1 by the frontcover portion 3 c covering the front side of the ultrasonic wave sensor1. Further, the splashes caused by front running cars can beintercepted.

In the first and second embodiments, the cover 3 attached to the bracket2 is formed, as shown in FIG. 8(A), which is a longitudinal sectionalview, such that the cover 3 does not intercept the path of theultrasonic waves SSW radiated from the radiator 1 a, 1 c and theultrasonic wave SSW detected by the detector 1 b, 1 d which are definedby the downwardly broadening conically shaped parts 1 h of the case body1 g (in the embodiments, broadening angle α=1200). The bracket 2 b isformed such that the flange part 2 b thereof is positioned offsettingrearward in the vehicle so that the lower end 3 d of the rear coverportion 3 b of the cover 3 is positioned higher than the path of theultrasonic wave indicated by double dashed line SSW. The height of therear cover portion 3 b is adjusted similarly. In the second embodiment,similarly the flange 2 b of the bracket 2 is positioned offsettingforward in the vehicle so that the lower end 3d of the front coverportion 3 c of the cover 3 is positioned higher than the path of theultrasonic wave indicated by the double dashed line SSW. The height ofthe front cover portion 3 c is adjusted similarly.

With respect to the side portion 3 a of the cover 3 attached to thebracket 2, as shown in FIG. 8(B), the cover 3 does not intercept thepath of the ultrasonic waves SSW which are defined by the downwardlybroadening conically shaped parts 1 h of the case body 1g and broadeningangle α=120° similarly as mentioned above referring to FIG. 8(A). Thebracket 2 is formed such that the flange part 2 k and the corner thereof2 h are positioned offsetting sideward (toward the wheel) in the vehicleso that the lower end 3 d of the side cover portion 3 a of the cover 3is positioned higher than the path of the ultrasonic wave indicated bythe double dashed line SSW. The height of the side cover portion 3 a isadjusted similarly. This is the same also in the case of the secondembodiment.

Such a configuration allows the ultrasonic wave SSW radiated from theultrasonic wave sensor 1 not to interfere with the cover 3 or bracket 2,so accurate detection of the inclination of the vehicle by means of theultrasonic wave sensor 1 is possible by preventing the contamination ofthe inclination sensor. Further, flying matter is intercepted by thecover 3, and the ultrasonic wave sensor 1 can be kept clean.

According to the present invention, flying matter such as muddy waterscattered by the rotating wheels of the running vehicle itself areprevented from advancing toward the ultrasonic wave sensor,contamination caused by impingement of the flying matter against theradiating faces of ultrasonic wave radiators and the detecting faces ofultrasonic wave detectors are prevented, and hence false detection ofthe inclination of the vehicle due to such contamination can be evaded,and appropriate adjustment of the light axes of head lamps is madepossible. By adjusting the light axes of the head lamps based on theoutput of the inclination sensor, accurate control of the axes of thehead lamps is possible.

1. A vehicle provided with an inclination sensor for detecting aninclination of the vehicle to a road surface, wherein said sensor isattached onto an undersurface of the vehicle at a position between thewheels in a direction of a width of the vehicle, and a cover memberhaving at least either of a side cover portion for covering the wheelside of the inclination sensor or a rear side portion for covering therear side of the inclination sensor is provided.
 2. The vehicle providedwith an inclination sensor according to claim 1, wherein saidinclination sensor is fixed to the vehicle by a bracket to which saidcover member is attached detachably.
 3. The vehicle provided with aninclination sensor according to claim 2, wherein said inclination sensoris an ultrasonic wave sensor comprising ultrasonic wave radiators forradiating an ultrasonic wave, ultrasonic wave detectors for detectingthe ultrasonic wave, and a case in which the ultrasonic wave radiatorsand ultrasonic wave detectors are mounted; the case is formed to haveconically shaped parts, each broadening in diameter from each of theultrasonic wave radiators and detectors toward the road surface, andsaid cover member is located such that the lower end thereof does notinterfere with each of the extension of the conically shaped parts. 4.The vehicle provided with an inclination sensor according to claim 1,wherein a head lamp controller is provided for controlling the lightaxes of the head lamps of the vehicle.
 5. The vehicle provided with aninclination sensor according to claim 1, wherein said inclination sensoris a laser sensor.
 6. The vehicle provided with an inclination sensoraccording to claim 3, wherein two pairs of ultrasonic wave radiators andultrasonic wave detectors are attached to said case, each pairconsisting of an ultrasonic wave radiator and an ultrasonic wavedetector.
 7. The vehicle provided with an inclination sensor accordingto claim 3, wherein said downward broadening part is formed to have abroadening angle of 120°.
 8. The vehicle provided with an inclinationsensor according to claim 3, wherein a head lamp controller is providedfor controlling the light axes of the head lamps of the vehicle.